# Copyright (c) 2006,2007 Mitch Garnaat http://garnaat.org/
#
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish, dis-
# tribute, sublicense, and/or sell copies of the Software, and to permit
# persons to whom the Software is furnished to do so, subject to the fol-
# lowing conditions:
#
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABIL-
# ITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
# SHALL THE AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, 
# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
# IN THE SOFTWARE.

import urllib
import mimetypes
import md5
import os
import rfc822
import StringIO
import time
import base64
import boto
import boto.utils
from boto.exception import S3ResponseError, S3DataError
from boto.s3.user import User

class Key:

    DefaultContentType = 'application/octet-stream'

    def __init__(self, bucket=None):
        self.bucket = bucket
        self.metadata = {}
        self.content_type = self.DefaultContentType
        self.filename = None
        self.etag = None
        self.key = None
        self.last_modified = None
        self.owner = None
        self.storage_class = None
        self.md5 = None
        self.base64md5 = None
        self.path = None

    def startElement(self, name, attrs, connection):
        if name == 'Owner':
            self.owner = User(self)
            return self.owner
        else:
            return None

    def endElement(self, name, value, connection):
        if name == 'Key':
            self.key = value
        elif name == 'ETag':
            self.etag = value
        elif name == 'LastModified':
            self.last_modified = value
        elif name == 'Size':
            self.size = value
        elif name == 'StorageClass':
            self.storage_class = value
        elif name == 'Owner':
            pass
        else:
            setattr(self, name, value)

    def get_metadata(self, key):
        return self.metadata[key]

    def set_metadata(self, key, value):
        self.metadata[key] = value

    def update_metadata(self, d):
        self.metadata.update(d)
    
    def generate_url(self, expires_in, method='GET', headers=None):
        path = '/%s/%s' % (self.bucket.name, self.key)
        path = urllib.quote(path)
        return self.bucket.connection.generate_url(expires_in, method,
                                                   path, headers)
    
    def send_file(self, fp, headers=None):
        http_conn = self.bucket.connection.connection
        if not headers:
            headers = {}
        headers['Content-MD5'] = self.base64md5
        if headers.has_key('Content-Type'):
            self.content_type = headers['Content-Type']
        elif self.path:
            self.content_type = mimetypes.guess_type(self.path)[0]
            if self.content_type == None:
                self.content_type = self.DefaultContentType
            headers['Content-Type'] = self.content_type
        else:
            headers['Content-Type'] = self.content_type
        headers['Content-Length'] = self.size
        final_headers = boto.utils.merge_meta(headers, self.metadata);
        path = '/%s/%s' % (self.bucket.name, self.key)
        path = urllib.quote(path)
        self.bucket.connection.add_aws_auth_header(final_headers, 'PUT', path)
        #the prepending of the protocol and true host must occur after
        #the authentication header is computed (line above). The
        #authentication includes the path, which for authentication is
        #only the bucket and key
        if self.bucket.connection.use_proxy:
            path = self.bucket.connection.prefix_proxy_to_path(path)
        http_conn.putrequest('PUT', path)
        for key in final_headers:
            http_conn.putheader(key,final_headers[key])
        http_conn.endheaders()
        try:
            l = fp.read(4096)
            while len(l) > 0:
                http_conn.send(l)
                l = fp.read(4096)
            response = http_conn.getresponse()
            body = response.read()
        except Exception, e:
            self.bucket.connection.make_http_connection()
            print 'Caught an unexpected exception'
            raise e
        if response.status != 200:
            raise S3ResponseError(response.status, response.reason)
        self.etag = response.getheader('etag')
        if self.etag != '"%s"'  % self.md5:
            raise S3DataError('Injected data did not return correct MD5')

    def _compute_md5(self, fp):
        m = md5.new()
        s = fp.read(4096)
        while s:
            m.update(s)
            s = fp.read(4096)
        self.md5 = m.hexdigest()
        self.base64md5 = base64.encodestring(m.digest())
        if self.base64md5[-1] == '\n':
            self.base64md5 = self.base64md5[0:-1]
        self.size = fp.tell()
        fp.seek(0)

    def set_contents_from_file(self, fp, headers=None, replace=True):
        if hasattr(fp, 'name'):
            self.path = fp.name
        if self.bucket != None:
            self._compute_md5(fp)
            if self.key == None:
                self.key = self.md5
            if not replace:
                k = self.bucket.lookup(self.key)
                if k:
                    return
            self.send_file(fp, headers)

    def set_contents_from_filename(self, filename, headers=None, replace=True):
        fp = open(filename, 'rb')
        self.set_contents_from_file(fp, headers, replace)
        fp.close()

    def set_contents_from_string(self, s, headers=None):
        fp = StringIO.StringIO(s)
        self.set_contents_from_file(fp, headers)
        fp.close()

    def get_file(self, fp, headers=None):
        if not headers:
            headers = {}
        http_conn = self.bucket.connection.connection
        final_headers = boto.utils.merge_meta(headers, {})
        path = '/%s/%s' % (self.bucket.name, self.key)
        path = urllib.quote(path)
        self.bucket.connection.add_aws_auth_header(final_headers, 'GET', path)
        #the prepending of the protocol and true host must occur after
        #the authentication header is computed (line above). The
        #authentication includes the path, which for authentication is
        #only the bucket and key
        if (self.bucket.connection.use_proxy == True):
            path = self.bucket.connection.prefix_proxy_to_path(path)
        http_conn.putrequest('GET', path)
        for key in final_headers:
            http_conn.putheader(key,final_headers[key])
        http_conn.endheaders()
        resp = http_conn.getresponse()
        if resp.status != 200:
            raise S3ResponseError(resp.status, resp.reason)
        response_headers = resp.msg
        self.metadata = boto.utils.get_aws_metadata(response_headers)
        for key in response_headers.keys():
            if key.lower() == 'content-length':
                self.size = response_headers[key]
            elif key.lower() == 'etag':
                self.etag = response_headers[key]
            elif key.lower() == 'content-type':
                self.content_type = response_headers[key]
            elif key.lower() == 'last-modified':
                self.last_modified = response_headers[key]
        l = resp.read(4096)
        while len(l) > 0:
            fp.write(l)
            l = resp.read(4096)
        resp.read()

    def get_contents_to_file(self, file, headers=None):
        if self.bucket != None:
            self.get_file(file, headers)

    def get_contents_to_filename(self, filename, headers=None):
        fp = open(filename, 'wb')
        self.get_contents_to_file(fp, headers)
        fp.close()
        # if last_modified date was sent from s3, try to set file's timestamp
        if self.last_modified != None:
            try:
                modified_tuple = rfc822.parsedate_tz(self.last_modified)
                modified_stamp = int(rfc822.mktime_tz(modified_tuple))
                os.utime(fp.name, (modified_stamp, modified_stamp))
            except Exception, e: pass

    def get_contents_as_string(self):
        fp = StringIO.StringIO()
        self.get_contents_to_file(fp)
        return fp.getvalue()

    # convenience methods for setting/getting ACL
    def set_acl(self, acl_str):
        if self.bucket != None:
            self.bucket.set_acl(acl_str, self.key)

    def get_acl(self):
        if self.bucket != None:
            return self.bucket.get_acl(self.key)

    
